1. K38e - A Very Brief History of Our Understanding of Human-Caused Greenhouse Warming of Earth

2. Mathematician Joseph Fourier first realized that our atmosphere induces a Greenhouse Effect in 1830

3. John Tyndall published papers showing that our own CO2 would block outgoing IR and thereby raise the temperature of the Earth, in 1850. The spectrum of water vapor and CO2 in the far IR was not well known enough to calculate the exact amount of warming

4. Svante Arrhenius, Swedish physicist, first calculated in 1895 the amount of the temperature effect on climate of adding our CO2 emissions

5. Svante Arrhenius, wins Nobel Prize in Chemistry in 1903

6. Guy Callendar Links Observed Rising Earth Temperatures to Fossil Fuel Burning and CO2, in 1938

7. 1958 – Charles Keeling Begins Landmark Recordings of Atmospheric CO2 with Unprecedented Precision

8. In 1988, GISS Head Dr. James Hansen Warns Congress that the Evidence is Compelling for Taking Action to Halt Human-caused GHG Climate Change

9. ~1990 – Formation of the IPCC and Plan to Issue Assessment Reports (AR) Roughly Every 5 years (UN Intergovernmental Panel on Climate Change) AR1 in 1990 AR4 published in 2007 AR5 published in 2013 Each report more serious and more convinced, even given the political fingerprints from the UN government reps and “volunteers” who must sign off on all AR’s

10. Late 20 th Century – Climate Denialism and Smear Campaigns Against Climate Scientists Begin

11. Hansen’s Family. Sophie (lower left) had the greatest influence on Hansen’s decision to Leave GISS in order to take up climate activism, given Corporate/Govt anti-science. He still does science, at Columbia University

12. Hansen’s been arrested a half-dozen times since 2009, at protests

13. And Today… (from the Mauna Loa Observatory for CO2, Apr ‘16) “We are now witnessing the fastest growth rates of the entire record of CO 2 measurements. This record-breaking growth is an expected consequence of the near record- breaking fossil fuel usage combined with the largest El Niño event in several decades. The very recent bump up in CO 2 levels recorded at Mauna Loa Observatory is not entirely unexpected because there is often significant uptick in CO 2 near the beginning of April before concentrations peak in May. This bump presumably reflects the fact that soils start to warm well before vegetation greens up in spring. The soil warming allows CO 2 to be emitted as organic matter such as compost decomposes. In a matter of weeks this soil emission will be offset by photosynthetic uptake, as the vegetation starts to turn on.”

15. And Today…

16. Key Points: K38f Very Brief History of Understanding of Human-Caused Climate Change Greenhouse Effect first realized in early 1800’s by Fourier First quantitative calculation by Arrhenius in 1895 Callendar Links fossil fuel burning, CO2 and Observed Rising Global Temperatures in 1938 1950’s US Military research supporting heat-seeking missile technology defines precise absorption spectra of CO2 and water vapor throughout Earth’s atmosphere, allowing more precise climate calculations thereafter 1990 IPCC AR1, Kyoto Accords first global summit to lower GHG’s Since then, corporate/political climate denialism continues to stymie any serious efforts, despite much improved science and vastly more dire predictions for the future